Stencil duplicating machine



March 3l, 1931. G, E CREED STENCIL DUPLICATING MACHINE Filed March 27, 1930 2 Sheets-Sheet l reef/r /NveNn a March 3l, 1931. G El @REED 1,798,371

l STENCIL DUPLICATING MACHINE Filed March 27, 1930 2 Sheets-Sheet 2 l N Ven 1702 Patented Mar. 31, 1931 UNITED STATES PATENT oFFicE GEORGE ERNEST CREED, on LoNDoN, ENGLAND, AssIGNon To n. GEsrnTNEn Limrrnn,

. or LONDON, ENGLAND STENGIL DUAPLICATING MACHINE Application led March 27, 193,0, Serial No This invention relatos to duplontns mncliines of the kind in which a stencil secured to a flexible stencil carrier is caused to. travel over a plurality of inking cylinders.

5 is well known the stencils employed in such machines are provided with a heading usually formed of relatively stiff paper designed to be engaged by stencil fastening means secured'to endless flexible bands or lo chains in driving engagement with the ends of the inking cylinders,y

This stencil fastening means in existing arrangements is a rigid member of a width substantially equal to the width of the stencil i5 heading andit` is secured rigidly at each end to a link provided in one of the lchains or bands. Y

The object of the present invention is to provide an improved connection between the 2o stencil heading and the endless flexible chains or bands.

According to the invention the connection is such that the stencil heading is free to move within suitable limits relatively to the links 25 engaging the'stencil fastening meansabout an axis parallel with the axes of the inking cylinders.

' ln other words, a degree of freedom of mo,- tion ofthe stencil heading about an aXis parallel with the axes of the inking cylinders relative to the link or immediately adjacent portion of the endless flexible members to which it is connected is provided Thus, in accordance with the invention, the stencil fastening means is secured to links, connected with bands or chains to form an endless flexible member, by a pivotal connection enabling the stencil fastening means to move within desired limits about the axis of the pivotal 'connection relatively to the links with which it is associated. Y It is found unnecessary to arrange the stencil fastening means so as to provide complete freedom of motion of the same relatively to the links and consequently stops, adapted to limit such motion, may be provided on the links.

Conveniently, the members provided on the links adapted to form bearings for the pivots may also be arranged to operate to as- -439,4 5,1, and in Groot @sittin ,11W 4, 192% sist in positioning or centralizing the stencil fastening means and consequently the stencil and they may also act in assisting the cor? responding location or positioning of the carrier which is arranged between the stencil and the nkns .oyllnots-Y i In ono oonstruoton in.. aooordnnoo with tho invention, the links to which the stencil fastening means is connected may each' beprovided on one side',I namely thej side directed l inward and towards the median plane ofthe machine, with a iiange or lug which lioles are provided adapted to function as bearings forth@ pvotS of tho otonol footningnioanls and these lugs at a pointy suitably remote vfrom e5 the aforesaid bearings maybe arranged to 'l provide sono Within which. lntoral oXtonSonS of the stencil fastening means will be located and by Whoh tho motion. ot tno. sont@ @bont its pivotal connection with the links' will he 70 lmtod- Further, tho, luso donor" operate no i abutments or lateral guides co-o erating with flanges provided on the head o the silk carrier inrorder appropriately to positiontlie same relatively to the inking cylinders. 'g5

Conveniently, the pivots of theY stencil fastening means are arranged to be engaged with the links, while the endless flexible members of which they form elements are in driving connection with the inking cylinders.

Thus, in accordance with the invention, the pivots onthe stencil fastening means may be associated with the same in snch manner that ono of tho pivots oon bo engaged in n link and the stencil fastening means moved laterally to enable the pivot at the opposite side of the stencil fastening means: to be Y engaged in the bearing provided therefor.

To this end, about one of the pivots a spring may be located while about the other there is provided a liked sleeve or stop in such manner that when the pivot with which tho Spring iS ossooietod is inserted, in its bearing tho Stencil fastening ineens may bo moved laterally in opposition to the spring in order that the pivot at the opposite side of the stencil fastening means may be entered in its bearing so that on subsequently Permitting tho yStonol fastening ineens to moro under tho .aotonof tho .Spring it will 10 be secured in position with respect to the links and the inking cylinders.

For limiting the motion of the stencil fastening means relatively to the links and about its pivotal connection therewith lateral extensions, as above indicated, may be provided on the stencil fastening means which will engage in gaps formed in the lugs provided on the links or between the lugs and the links of which they form part,

The invention will be described further in detail with reference to the accompanying drawings, in which Figure 1 is a fragmentary view in front elevation of a duplicating machine;

Figure 2 is a diagrammatic view in end elevation of a duplicating machine provided with the invention, certain portions being removed to assist in the disclosure;

Figure 8 is a detailed view on a larger scale showing the construction of the stencil fastening` means illustrated in Figure 1, and

Figure e is a fragmentary7 View of a stencil sheet adapted to be engaged by the stencil fastening means in question.

In the drawings, referring to Figure 1, 1 and 1a are the side members of the frame of the machine, 2 is a handle whereby, through the intermediary of the wheels 3 and 4f, the inking cylinder 5 may be rotated, the inking cylinder 5a being driven therefrom by the flexible bands 6 which engage projections 7 and 7a on the respective ends of the inking cylinders. To the ends of the flexible bands are secured links 8, each of these links being provided with a flange or lug 9 the form of which can be more clearly seen in Figure 2. Each of the lugs is furnished with a hole in which the opposite ends of the pivot 10 of the stencil fastening means are engaged, one end of this pivot being provided with a` stop 11 and at the other end with a. spring 12 in such manner that when the pivot with which the latter is associated is inserted in the hole in a lug, the stencil fastening means may be moved laterally, that is to say, axially with respect to the pivot in opposition to the spring to facilitate insertingi the pivot at the opposite end of the stencil fastening means in the hole in the lug which it is designed to engage.

The pivots in question are constituted by the ends of a rod 18 pivotally connecting together the upper member 14 and the lower member 15 of the stencil fastening means, a spring 16 being associated with these two members in such manner as to constrain them to move about their pivotal connection to secure engagement of the stencil sheet.

The stencil fastening means illustrated and described above is designed -to engage a stencil heading of the form shown in Figure 4. in which 17 indicates the main body of the stencil heading, provided with displaceable tongues 18 and forming an extension of the backing sheet 19 and 20 being the sheet of stencilizable material secured thereto.

The tongues in question are arranged to be disglaced by the members 21 provided on the lower member 15 of the stencil fastening means and thereby caused to abut against the abutment surfaces 22 on the upper member of the stencil fastening means. With the lower member of the means in. question is secured a flexible foraminous sheet 23, one end of which is secured to a rigid member 24 in known manner, the ends of this rigid member being permanently engaged with springs 25, the ends of which are formed with loops adapted to engage links 26 slidable upon pins 27 provided on the rigid member 28 which, by means of a piece of flexible non-porous material 29, is engaged with the stencil fastening means.

On the lower member 15 of the stencil fastening means two lugs or lateral extensions 30 are provided. which engage in gaps or recesses 31 so dimensioned as to permit a desired degree of pivotal motion of the stencil fastening means about the axes of the pivots 10 and 11 as is indicated in Figure 2.

As by the pivotal connection of the stencil heading with the links in the bands or chains a degree of motion of the stencil heading is permitted the slack in the stencil which is formed as the direction of travel of the stencil heading changes from a circular to a rectilineal path is taken up at least in part by the movement of the stencil fastening means about its pivot.

The degree of buckling of the stencil sheet is consequently reduced and this operates to increase the life7 of the stencil.

The means above described may be regarded as illustrative of a suitable means for reducing such buckling of the stencil and the invention may, therefore, be stated to consist broadly in the provision of means to this end as obviously any suitable device or arrangement causing or permitting the stencil fastening means to move the stencil for taking` up such slack or buckle such as a spring mounting may be employed.

The stencil fastening means may be generally of the character described in the specifications of the applications for British Letters Patent Nos. 37,658, 37,659 and 37,660 of 1928 in so far as the means for engaging the stencil and the silk carrier are concerned and the substantially rigid member forming the head of the latter and the means whereby it is connected with the machine may be provided with upturned ends adapted to bear against the lugs on the links.

As will be understood, the above description is furnished for the purpose of describing the nature of the invention and for the purpose of particularly describing and as certainin a suitable manner of carrying the same into effect, consequently the details of construction and arrangement above referred to may be varied within wide limits without exceeding the scope of the invention which moreover is not to be regarded as necessarily limited by the modes of expression employed in defining what at this date are regarded as its important features.

Having now described my invention, what I claim as new and desire to secure by Letters Patent is l. Stencil fastening means for duplicating machines of the kind in which a plurality of inking cylinders are provided and in driving connection with the ends of said cylinders are endless flexible members furnished with links to which is secured the stencil fastening means adapted to engage a stencil heading provided on the stencil comprising as a connection between the stencil fastening means and the flexible members, means adapt* ed to permit the stencil heading when engaged by the stencil fastening means to move relatively to the flexible members about an axis parallel with the axes of the inking cylinders.

2. Stencil fastening means for duplicating machines of the kind in which a plurality of inking cylinders are provided and in driving connection with the ends of said cylinders are endless flexible members furnished with links to which the stencil fastening means adapted to engage a stencil heading provided on the stencil is secured comprising, as a connection between the stencil fastening means and the links, means adapted to permit a limited degree of movement of the stencil fastening means relatively to the links about an axis parallel with the 'axes of the inking cyliners.

3. Stencil fastening means for duplicating machines of the kind in which a plurality of inking cylinders are provided, in driving connection with the ends of said cylinders are endless flexible members furnished with links to which the stencil fastening means is secured comprising a pivotal connection whereby the stencil fastening means is connected with the endless flexible members.

4. Stencil fastening means for duplicating machines of the kind in which a plurality of inking cylinders are provided, in driving connection with the ends of said cylinders are endless flexible members furnished with links to which the stencil fastening means is secured comprising a pivotal connection whereby the stencil fastening means is connected with said links.

5. A stencil fastening means for duplicating machines of the kind in which a plurality of inking cylinders are provided and in driving connection with the ends of said cylinders are endless flexible members furnished with links to which the stencil fastening means is secured comprising a pivot on each of its ends adapted to engage bearings provided on the endless flexible members.

6. Means for securing a stencil in position on a duplicating machine of the kind including a plurality of inking cylinders in which a stencil provided with a stencil heading is adapted to be secured by said heading to endless flexible members in driving engagement with the ends of the plurality of inking cylinders comprising apivotal connection between the stencil fastening means and the endless flexible members adapted to permit the stencil fastening means to move about an axis parallel with the axes of the inking cylinders.

7. A duplicating machine comprising a plurality of inking cylinders, endless flexible members in driving connection with the ends of the inking cylinders, a link in each of said endless flexible members, a bea-ring element on each of said links, means adapted to engage the stencil heading and a pivotal connection between said means and the bearing members in said links.

8. A duplicating machine comprising a plurality of inking cylinders, endless flexible members in driving connection with the ends of the inking cylinders, a link in each of said endless flexible members, a bearing element on each of said links, means adapted to engage the stencil heading, a pivotal connection between said means and the bearing members in said links, an elevation on each of said links, a recess in each of said elevations and a projection on each end of the stencil fastening means adapted freely to engage in the recess in the adjacent link to permit a limited degree of motion of the stencil fastening means about the axis of its pivotal connection with the links.

9. A duplicating machine comprising a plurality of inking cylinders, endless flexible members in driving connection with the ends of the inking cylinders, a link in each of said endless flexible members, a perforated flange on each of said links, means adapted to engage the stencil heading of the stencil 'and to extend from side to side of the machine, a pivot on each of the two opposite ends of said means pivotally engaged in the perforated anges, projections on each of the two opposite ends of said means and recesses in the flanges freely engaged in the projections and adapted to permit motion thereof within the limits of said recesses and thereby to permit motion of the means adapted to engage the stencil heading about the axis of its pivotal engagement with the links.

In testimony whereof I have signed my name to this specification.

GEORGE ERNEST CREED. 

